The present invention relates to a photographic roll film camera with a spoolless film take-up chamber.
Photographic roll film cameras of the above-mentioned general type are known in the art. Known photographic cameras have the above-mentioned spoolless take-up chamber provided with film roll forming means, and also transporting means for transportation of film from a supply chamber or a supply cartridge into the take-up chamber and back into the supply chamber or cartridge. One of such cameras is disclosed, for example, in the German Pat. No. 1,115,571. A perforated roll film is transported by a perforation wheel from a supply cartridge into the take-up chamber and then is transported back into the cartridge, in accordance with the construction disclosed in this patent. A spiral serves as the roll-forming means in the spoolless take-up chamber. In accordance with DE-GMS Pat. No. 1,952,673, the roll-forming means for such a camera is formed as a slide foil band which has, in closed condition of the camera, a cylindrical roll-forming loop. Cylindrical spring loops are also known as roll-forming means in the spoolless film cartridges. The operability of the above-described known roll-forming means depends very much upon their spring or slide characteristics. Thereby their utilization in cameras in which, contrary to the spoolless film cartridges, they must function for years, is not satisfactory. On the other hand, utilization of high-grade materials for these means and their exact shape makes them very expensive.
The German Pat. No. 1,294,108 deals with a roll film camera with an automatic film threading device which has a springy guiding plate which can be supported turnable and closes the film take-up chamber from the rear cover, and also a springy arcuate guiding lever with a concave surface directed against a film spool in the take-up chamber. Thereby, the initial portion of the film after entering between a film gate and the guiding plate is pressed against the engaging means of the film spool and suspended on the latter during rotation of the film spool. The guiding lever has at its end a roller in the region of the film perforations so as not to damage the film and to hold the friction between the film and the guiding lever during increase of the film roll diameter as long as possible. In its initial position, the guiding lever or its roll abuts against the outer surface of the take-up spool. This automatic film threading device better copes with the above-described problems and has a considerably greater service life than the other roll-forming means. However, it is not suitable for spoolless film take-up chambers.